Today we're going to open Pandora's box. We're going to point the skeptical eye at AGW, anthropogenic global warming, that part of of climate change due to human actions. There's little dispute that climate change is real and natural; over the millennia, global climate patterns have gradually shifted. There's little dispute about natural global warming; we've been warming up for 150 years since the last lows of the Little Ice Age. But what there's plenty of dispute about — at least within the public if not within the scientific community — is AGW. How much are we humans causing or increasing the warming? What will the effects be of that increase if it exists? What, if anything, should we do about it?

Public understanding of AGW is all messed up, way more so than any other science, even more messed up than creation vs. evolution. The reason is obvious to everyone: It's never really been a science issue in the public's mind; it's a political issue. It's a political hot potato that has everyone on both sides of the aisle fired up and raging with conspiracy theories, fraud charges, end of the world scenarios, scandals and corruption. The result is that almost nobody in the public has a detailed understanding of the real science, yet almost everyone who follows the issue takes a side with great passion, either embracing AGW or dismissing it. What went wrong? How and why did this important science fly off the tracks and fall into the pit of politics?

This happened because AGW was never presented to the public the way science is; it was first presented as a political issue. The 1997 Kyoto Protocol, which made headlines when it went into effect in 2005, was the first time most people in the general public had any idea that global warming was a thing. Kyoto was a United Nations plan to reduce industrial emissions, but only in the wealthiest countries, and not at all in the biggest, poorest, dirtiest countries (China and India). It was deeply flawed scientifically, and effective really only as a slap in the face to the United States. Industrial powers, large on the political right, opposed it; environmental powers, largely on the left, supported it.

The second time the general public heard about global warming was also unscientific. Al Gore's 2006 movie An Inconvenient Truth was the first time that almost everyone had ever heard of global warming, and it was perceived as either gospel or as lies purely because of Al Gore's highly polarized position in the political world. Gore was a great champion of the Kyoto Protocol, and so was already perceived by conservatives more as an enemy of capitalism than as a defender of the environment. Whether anything he said was true or not, enough people went into the theaters predisposed to either embrace whatever he said or to reject whatever he said, that the actual content (even the whole subject itself) made little difference.

And that's exactly what got us where we are. By far the strongest predictor of a person's stance on global warming is his or her political affiliation. AGW is the poster boy of failed science communication. It is the perfect example of people embracing bad science because it agrees or disagrees with an ideology, either political or philosophical or ecological.

Think for a minute what would have happened if global warming had first been publicized by Stephen Hawking. I use Hawking as an example because he's really the only scientist who's known all around the world, and is universally respected and trusted. When Stephen Hawking tells you a science fact, you say "That's good enough for me." I would. And, like you, I haven't the slightest idea what Stephen Hawking's politics are. It's never occured to me and I couldn't care less. Even though he's not at all a climate scientist, he's trusted by John Q. Public on matters of science, unlike Al Gore. If Stephen Hawking had been the one to make a movie about AGW instead of Al Gore, we might have no AGW denial at all in the world.

In this episode, I am not going to try to convince anyone of anything by reading off lists of temperature measurements or CO2 levels, or in fact give any facts and figures at all. Why not? Because that technique is a proven failure. Very few people have come to a conclusion on AGW that's fully independent of their ideology due to careful, impartial study of data. And for those who have, who knows whose interpretation of data they were studying? It's very easy to spin any data to show just about anything you want. A layperson Skeptoid listener has no way to know whether the facts and figures I'd give (or that anyone else might give) are in line with the AGW supporters, or with the AGW opponents. My goal here is to give a layperson the tools to come to an unbiased conclusion that truly is based on the best state of our current knowledge. For those of you on the right, this means setting aside distrust of the left; and for those of you on the left, it means setting aside distrust of the right.

Let me throw a couple of statements at you, one that you're likely to agree with, and one that you're likely to disagree with:

Statement A: Conservatives tend to reject AGW because it conflicts with their political agenda.

Statement B: Liberals tend to embrace AGW because it fits nicely with their political agenda.

Most of you (not all of you) strongly disagree with what I just said about your ideology, and you strongly agree with what what I just said about the opposing ideology. Now about half of you are conservatives and about half of you are liberals, so at least half of you have to be wrong. If you have a truly open mind, you are open to the possibility that your own feelings on AGW are tempered with your ideology. It's probably fair to say that most people's are to some degree; it's perfectly fine to be satisfied when science facts fit nicely into your ideology. It's very difficult, and very rare, for any person's understanding of science to be completely divorced from their emotions or philosophies.

Name an expert you agree with on climate change. Almost nobody will name a real climate scientist; they'll name a communicator or pundit. In fact, name any climate scientist at all. None of them are famous; few of us have ever even heard one speak. Everything you know about climate science has been filtered through somebody else — probably someone you're predisposed to agree with.

So how can a layperson know what's probably right? As I always say on Skeptoid, go to our best scientific consensus and roll with that; you'll be right far more often than you'll be wrong. So this raises the obvious question: What is our best, real, apolitical, unbiased climate science consensus? Well, like it or not, the closest thing we have to that is the IPCC, the Intergovernmental Panel on Climate Change, established by the United Nations in 1988, a decade before the Kyoto Protocol was conceived and long before Al Gore ever heard of global warming. Now before you react, let's acknowledge some things. The IPCC is imperfect, and always has been. So is the prison system, so is the education system; every institution is a compromise of trying to please everyone. They're imperfect, but they're the best we're able to assemble. The criticisms are perfectly valid. It's not necessary to regard the IPCC as a perfect institution to accept the scientific consensus that it provides.

One facet that characterizes good science is that it evolves as our knowledge improves. In this way, the IPCC has produced four major versions of its assessment reports, and of as this writing is working on its fifth scheduled to be published in 2014. No responsible scientist has ever claimed that our current theories are absolutely correct and no further study is needed. The more work is done, the better our theories explain the observations. The tighter our predictions get. If you put any trust at all in the scientific method or in any branch of science, you know that our latest and best theories are just that. They're never final, they're never complete. It is not a weakness of the IPCC that they release revised assessment reports every few years; it's a strength. The constant publication of climate science articles in the best journals is not consistent with an old hoax, it's consistent with good science being done the way it's supposed to be done.

Is it possible that a synthesis of all the world's climate scientists is wrong about the science they spend their lives studying, and your favorite political commentators are right? Certainly it is. It's probably not very likely, but if it does turn out to be the case, then the synthesis will evolve in the direction that pans out through experimentation and observation, and future IPCC reports will be even closer to the facts.

Perhaps among the most flagrant mischaracterizations about AGW is that it's a long-debunked hoax or fraud, and that nobody takes it seriously anymore. This perspective reflects a total disconnect from current research. Fortunately, it's very easy to fix. Simply go to IPCC.ch (.ch is the top-level domain for Switzerland), click on the latest Assessment Report, and spend 10 minutes — or even 5 minutes — skimming the Summary for Policymakers. If you want to know the latest of the latest, go to the websites of the world's two leading scientific journals, Science and Nature. Search ScienceMag.org for the term "climate change" or look at Nature's sub-publication, Nature Climate Change. Take these minimal steps to inform yourself before telling anyone that AGW is a long-debunked hoax, or a fraud or a conspiracy. Such a perspective requires a deliberate disdain for current research.

One of George Carlin's most famous bits was titled The Planet Is Fine, in which he notes that no matter what kind of pollution humans produce, it really only affects those beings living there and not the planet itself. "The Earth isn't going anywhere," he says, "we are." Just where are we headed? Well, our best answers (so far) are there for you in black and white, if you're truly interested in knowing what they are.